package hadoop;

import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;

import java.io.IOException;

/**
 * @author Lu Ruotong
 * @date 2022/3/11 15:56
 */
public class WordcountMapper extends Mapper<LongWritable, Text,Text, IntWritable> {

    // 设置map 端输出的 类型
    Text k = new Text();
    IntWritable v = new IntWritable(1);
    // 快捷键：ctrl + o
    @Override
    protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
        // 1. 获取第一行
        String line = value.toString();
        // 2. 对数据进行切割 deer bear river
        String [] words = line.split("\t");
        // 3.输出
//     for (String word:words){
        if(words[4].equals("A")){
            k.set(words[4]);
            context.write(k,v);
        }

//     }
    }
}
